NASA, ESA, S. Gallagher (The University of Western Ontario), and J. English (University of Manitoba)

Release Date:

February 18, 2010

Note:

Spitzer and GALEX data were combined with the Hubble data to create the composite image. The Spitzer data were taken February 22, 2005 (PI: K. Johnson, University of Virginia/NRAO). The GALEX data were taken December 27, 2004 (archival data). A small amount of WFPC2 data (proposal 5900, PI: P. Conti) taken on October 7, 1995, was used to fill in a portion of the ACS/WFC chip gap in this composite image of HCG 31.

Color:

This image is a composite of separate exposures acquired by three separate space telescopes. Exposures in the optical range of the spectrum were acquired with ACS and WFPC2 instruments on the Hubble Space Telescope (HST). The near-ultraviolet light was acquired by the Galaxy Evolution Explorer (GALEX), while near-infrared emission was captured by the IRAC instrument on the Spitzer Space Telescope (SST). Several filters were used to sample these wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are: